Category Archives: Algebra

My 7th graders are working on “percentages of” problems currently, and late last night, I saw this problem on one of Don Steward’s handouts. There are 75 olives, 40% of which are green. I eat some of the green olives until 10% of the olives that remain are green. How many green olives did I […]

From CPM: The Sutton family took a trip to see the mountains in Rocky Mountain National Park. Linda and her brother, Lee, kept asking, “Are we there yet?” At one point, their mother answered, “No, but what I can tell you is that we have driven 100 miles and we are about 2/5 of the way there.” […]

We don’t cover quadratic in Math 8 this year, so we really can’t do Des-man. I come up with “Puppy House” instead so my students can still create something that allows them lots of practice with writing linear equations with domain and range restrictions. They draft the house on paper. The house needs to have a minimum of 6 […]

I’m always happy to hear how teachers use visualpatterns.org with their students. Michael Fenton shares how he uses the patterns with Desmos. And this. Alex Overwijk’s students use the big whiteboards. Whiteboard photos of http://t.co/ajYFLzRQSU that my S’s did yesterday….thanks @fawnpnguyen#mtbos#mathchatpic.twitter.com/UZd3HPfyoL — Alex Overwijk (@AlexOverwijk) March 7, 2015 Bridget Dunbar removes some figures, and […]

I know Common Core does not have absolute value in grade 8, but I’m teaching it anyway because we’re still doing “algebra 1” this year. (A year ago Raymond Johnson looked into the inclusion of this topic in the different grade levels.) My 8th graders know that the absolute value of 5 is 5, and the absolute […]

This year I’ve taken away a lot of my step-by-step instructions for the Barbie Bungee activity that I’d posted 1.5 years ago. They get no handouts, only some verbal instructions: See that gob of tape up there? That’s leftover tape from previous years where Barbie had taken her jump. It should be at 3 meters up. Well, […]

[NCTM Illuminations has my blessings and thanks to re-write and feature this lesson on their site.] Andrew Stadel and I recently presented this task at the 2013 CMC‘s North and South Conferences. The Challenge As a team, build a hotel that yields the highest profit [score]. Rules and guidelines for building the hotel Each cube represents a […]

I normally share a lesson that I’ve already done with students, but I’m still tweaking this one and needing to write some thoughts down before my noggin turns back into soft tofu. I bought these 14 pull-back friction toy cars (2 sets) for $30 at Costco. Amazon posts a video of how well these soft squeezable cars […]

[The title of this post in the old blog was actually “if there’s cold beer in the fridge.” It’s dumb, but I did end the post with “Forgive me for being such a delinquent, but my last day of school is not until June 21. I’m losing it.” So I have an excuse for everything.] Heya, back-to-back […]